Controls
must be designed and located within the reach, strength, and coordination
capabilities of the users. In the Introduction Module, anthropometric
and biomechanic principles were introduced. Controls are an excellent
example of how this knowledge is put to use.

Reach
- Reach to a control should be based on the shortest reach anticipated
in the worker population, typically the reach capabilities of
the 5th percentile female. The data point used should be for "functional
reach." Functional reach is not just the farthest point that
can be touched, but takes into consideration the need for hand
use for control activation.

Strength
- The strength required for control activation should be no more
than can be applied by the 5th percentile female.

Body
Size - In constrained spaces, access to controls should
be based on the body dimensions of the largest worker. Typically,
clearance space for each affected body dimension should be that
of the 95th percentile male. If it is possible that workers could
become entrapped because of size, then the 99th percentile measurements
should be used.

Coordination
- The coordination required for control and display use should
not exceed that which can be anticipated in the worker population.

Placement
of controls and the strength required for use must fit
the worker.*